Color Contrast - Check Contrast Online

Check color contrast according to WCAG

Sample Document - Sample Text

Result WCAG

21.00:1
Contrast ratio
AA Normal
≥ 4.5:1
AA Large
≥ 3:1
AAA Normal
≥ 7:1
AAA Large
≥ 4.5:1

Color Contrast Checker - Professional Free Online WCAG Contrast Check

Color contrast checking tool according to WCAG 2.1 standards of Tan Phat Digital. Calculate the exact contrast ratio from 1:1 to 21:1 using the W3C standard luminance formula. Check pass/fail for 4 standards: WCAG AA Normal (≥4.5:1), WCAG AA Large (≥3:1), WCAG AAA Normal (≥7:1), WCAG AAA Large (≥4.5:1). Preview realtime with sample text in Vietnamese and English. Intuitive color picker for foreground and background, direct hex code input. Button to quickly change foreground ↔ background color. Display pass/fail clearly with icons ✓ and ✗. Ensure accessibility for website and app, complying with WCAG 2.1 guidelines.

Outstanding features

Calculate the exact contrast ratio (1:1 to 21:1) according to the W3C formula
Check WCAG AA Normal text (≥4.5:1)
Check WCAG AA Large text (≥3:1)
Check WCAG AAA Normal text (≥7:1)
Check WCAG AAA Large text (≥4.5:1)
Preview realtime with sample text in Vietnamese and English
Intuitive color picker for foreground and background
Enter the hex code directly (#RRGGBB)
Button to change color foreground ↔ background
Display pass/fail clearly with icons ✓ and ✗
Result color: green (pass), red (fail)
Offline processing in browser

Why is color contrast important for web accessibility?

Color contrast is the most important factor in web accessibility related to color. If the font color and background color are too close to each other, many user groups will have difficulty reading: Low vision people - about 2.2 billion people in the world. Elderly people - vision decreases with age. Color blind people - 8% of men, 0.5% of women. Viewers in poor lighting conditions or low quality screens. WCAG (Web Content Accessibility Guidelines) developed by W3C regulates the minimum contrast ratio to ensure content can be read by everyone. WCAG compliance is not only ethical and inclusive design, but also a legal requirement in many countries (ADA in the US, EAA in the EU). Websites that are not accessible can be sued and fined.

Benefits when used

  • •Website accessible to all users including the visually impaired
  • •Comply with WCAG 2.1 guidelines - international standards
  • •Improved UX for the elderly and color blind
  • •Avoid legal risks regarding accessibility (ADA, EAA)
  • •Better SEO - Google prioritizes accessible sites
  • •Increase conversion rate - easier to read text = more engaged users
  • •Brand reputation - shows concern for all users
  • •Free unlimited use

Detailed instructions on how to check color contrast

  1. 1Select the font color (foreground) using the color picker or enter the hex code
  2. 2Select the background color using the color picker or enter the hex code
  3. 3See sample text preview with selected color above
  4. 4See automatically calculated contrast ratio (e.g. 4.5:1)
  5. 5Check pass/fail results for 4 WCAG standards
  6. 6If it fails, adjust the color to increase contrast
  7. 7Click
  8. 8to swap foreground ↔ background if needed
  9. 9Repeat for all color combinations on website

Cooperate immediately with Mavis Digital

We not only design websites, but also help businesses build strong digital brands. Providing comprehensive website design services from design to SEO optimization. Please contact Mavis Digital immediately to create breakthrough, effective and sustainable technology solutions for your business in Ho Chi Minh.

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